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High‐energy rechargeable lithium‐ion batteries, especially solid‐state lithium metal batteries, are increasingly required to operate at elevated temperatures in addition to pursuing operation at low temperatures. However, the notorious chemical and electrochemical reactions at the interface between the Li‐anode and solid state electrolyte (SSE) make these batteries lose almost all of their capacity and power at elevated temperatures. Here, a safe and long‐cycle‐life solid‐state Li–CO2 battery operating at elevated temperatures by constructing a stable and high ionic conductive molten salts interface (MSI) is reported. The MSI can effectively improve the interface contact and suppress interface reactions and the thermal runaway between Li‐anode and Li1.5Al0.5Ge1.5P3O12 (LAGP)‐electrolyte even at high temperatures, thus enabling an ultra‐low interface impedance (≈15 Ω) and discharge/charge overpotential (≈15 mV) for high temperature symmetric battery. In addition, the MSI‐coated LAGP‐electrolyte shows an ultra‐flat and continuous surface that enables a homogeneous Li tripping/plating during cycles. As a result, the Li symmetric battery shows superior cycling stability over 600 h at 0.1 mA cm−2 at 150 °C. The assembled solid‐state Li–CO2 battery using Ru catalysts shows outstanding cycle stability over 980 cycles at 150 °C, with a capacity limitation of 500 mAhg–1 at 500 mA g−1.

Aqueous rechargeable zinc (Zn)–air batteries have recently attracted extensive research interest due to their low cost, environmental benignity, safety, and high energy density. However, the sluggish kinetics of oxygen (O2) evolution reaction (OER) and the oxygen reduction reaction (ORR) of cathode catalysts in the batteries result in the high over-potential that impedes the practical application of Zn–air batteries. Here, we report a stable rechargeable aqueous Zn–air battery by use of a heterogeneous two-dimensional molybdenum sulfide (2D MoS2) cathode catalyst that consists of a heterogeneous interface and defects-embedded active edge sites. Compared to commercial Pt/C-RuO2, the low cost MoS2 cathode catalyst shows decent oxygen evolution and acceptable oxygen reduction catalytic activity. The assembled aqueous Zn–air battery using hybrid MoS2 catalysts demonstrates a specific capacity of 330 mAh g−1 and a durability of 500 cycles (~180 h) at 0.5 mA cm−2. In particular, the hybrid MoS2 catalysts outperform commercial Pt/C in the practically meaningful high-current region (>5 mA cm−2). This work paves the way for research on improving the performance of aqueous Zn–air batteries by constructing their own heterogeneous surfaces or interfaces instead of constructing bifunctional catalysts by compounding other materials.

Lithium‐carbon dioxide (Li‐CO2) batteries have attracted much attention due to their high theoretical energy density. However, due to the existance of lithium carbonate and amorphous carbon in the discharge products that are difficult to decompose, the battery shows low coulombic efficiency and poor cycle performance. Here, by adjusting the adsorption of carbon dioxide (CO2) on ruthenium (Ru) catalysts surface, this work reports an ultralow charge overpotential and long cycle life Li‐CO2 battery that consists of typical lithium metal, ternary molten salt electrolyte (TMSE), and Ru‐based cathode. Experimental results show that the Ru catalysts deposited on quartz nanofiber (QF) can suppress the four‐electron conversion of CO2 to lithium carbonate (Li2CO3). As a result, the battery shows a long‐cycle‐life of over 457 cycles at 1.0 A g−1 with a limited capacity of 500 mAh g−1Ru. Remarkably, a recorded low discharge potential of ≈3.0 V has been achieved after 35 cycles at 0.5 A g−1, with a charge potential retention of over 99%. Moreover, the battery can operate over 25 A g−1 and recover 96% potential. This battery technology paves the way for designing high‐performance rechargeable Li‐CO2 batteries with carbon neutrality.

Solid-state lithium-metal batteries using inorganic solid-state electrolyte (SSE) instead of liquid-electrolyte, especially lithium-oxygen (Li-O2) battery, have attracted much more attention due to their high-energy density and safety. However, the poor interface contact between electrodes and SSEs makes these batteries lose most of their capacity and power during cycling. Here we report that by coating a heterogeneous silicon carbide on lithium metal anode and LAGP-SSE, a good interface contact is created between the electrode and electrolyte that can effectively reduce the interface impedance and improve the cycle performance of the assembled battery. As a result, the solid-sate Li-O2 battery demonstrates a cycle lifespan of ~78 cycles being at least 3-times higher than the solid-state Li-O2 battery without silicon carbide with a capacity limitation of 1000 mAhg-1 at 250 mA g-1. The characterization of discharge products indicates a typical two-electron convention of oxygen-to-lithium oxide for the solid-state Li-O2 battery system. This work paves a way for developing high-energy long-cycle solid-state lithium-metal battery. The work provides insights into the interface between the Li-metal and SSE to develop high-energy long-cycle all solid-state Li-metal batteries.

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